This invention relates generally to four cycle internal combustion engines and more particularly to an intake manifold arrangement for supercharging the combustion chamber without the use of gears, impellers and/or mechanical pump. More specifically, the invention is directed to an intake manifold arrangement wherein the air and fuel supply first travels through an adjustable check valve, a pressure chamber and then through the intake valve and into the combustion chamber.
In the past, supercharging of a combustion chamber has been done by using various mechanical pumps to pressurize the air and fuel mixture prior to its entering the combustion chamber. This method of supercharging, however, must use a portion of the engine output power to drive the gears, impellers, and/or mechanical pumps. Accordingly, the overall efficiency of the supercharged engine is decreased. A disadvantage to mechanical pump-type superchargers is that they are often mechanically complex and subject to failure. In the case of exhaust gas driven superchargers, oil tends to cake on the impeller bearings if not properly cooled down before shutting off the engine.
Furthermore, in the past, preheating of the fuel and air mixture has been done externally of the combustion chamber where the temperatures for heating the fuel and air mixture are lower than the temperature of the combustion chamber wall and the immediate vicinity. Thus, the fuel and air mixture has not been heated and vaporized to the fullest extent possible whereby it can be burned in the most efficient manner. Accordingly, internal combustion engines have not been efficient due to inefficient burning of fuel. Many prior art fuel preheaters require an external source of energy, such as battery powered electrical heating elements.
In conventional engines, the spent fuel within the combustion chamber is exhausted by the pistons traveling to top dead center during the exhaust stroke. In some cases, as shown in U.S. Pat. No. 3,046,961, residual exhaust gases have been removed from the combustion chamber by a charge of fresh air being forced into the combustion chamber substantially at the top thereof at about the top dead center position of the piston. As can be appreciated, this is not very efficient because the charge of air introduced at the top of the cylinder near top dead center does not necessarily cause exhaust gases near the piston, during the beginning of the exhaust stroke, to exit through the exhaust valve.